In the kingdom, the Champignon Witch, Luna, has lived alone in her cottage deep within the Black Forest for generations. Known for the toxic mushrooms that grow where she walks, Luna rarely leaves her isolation, venturing to town only to distribute medicine. As a black witch, Luna must remain inconspicuous to evade execution, as the kingdom only tolerates white witches.
Her isolated life takes a turn when she saves Lize, a boy on the brink of death. Luna learns that Lize is destined to become The End of All Things and decides to take him under her wing, steering him away from a malevolent fate. To protect Lize from being put to death, Luna must now teach him magic despite her own limitations.